Mathias Verraes mathiasverraes

https://github.com/rikvdkleij/intellij-haskell

General setup

Install latest versions of ghc-mod and haskell-docs;
Set file paths to ghc-mod, hlint, stack and haskell-docs in the menu Settings/Other Settings/Haskell.
Be sure in Editor/Filetypes that Haskell language file is registered with pattern *.hs and Literate Haskell language file with pattern *.lhs;

Project

Category theory jargon cheat sheet

A primer/refresher on the category theory concepts that most commonly crop up in conversations about Scala or FP. (Because it's embarassing when I forget this stuff!)

I'll be assuming Scalaz imports in code samples, and some of the code may be pseudo-Scala.

Functor

A functor is something that supports map.

GitHub provides a special pulls remote "namespace" on the upstream repo, so you can add it as a fetch pattern to your .git/config like so:

    [remote "upstream"]
      url = https://github.com/neovim/neovim.git
      fetch = +refs/heads/*:refs/remotes/upstream/*
      fetch = +refs/pull/*/head:refs/pull/upstream/*

Then when you git fetch --all, you will have ALL pull requests available in your local repo in the local pull/ namespace. To check out PR #42:

	BEGIN:VCALENDAR
	VERSION:2.0
	PRODID:-//www.marudot.com//iCal Event Maker
	X-WR-CALNAME:Domain-Driven Design Europe 2017
	CALSCALE:GREGORIAN
	BEGIN:VTIMEZONE
	TZID:Europe/Berlin
	TZURL:http://tzurl.org/zoneinfo-outlook/Europe/Berlin
	X-LIC-LOCATION:Europe/Berlin
	BEGIN:DAYLIGHT

	module Bowling where

	import Test.QuickCheck
	import Data.List

	data Frame =
	Roll Int Int
	\| Spare Int Int
	\| SpareExtra Int
	\| Strike

	(define (f a b c)
	(sum (map sq (max2 a b c)))
	)

	(define (biggest a b)
	(if (> a b) a b)
	)

	(define (sq a) (* a a))

	-- in reaction to http://codemanship.co.uk/parlezuml/blog/?postid=1325

	-- oneHundredIntegersSeparatedByCommas
	-- integersDivisibleByThreeReplacedWithFizz
	-- integersDivisibleByFiveReplacedWithBuzz
	-- integersDivisibleByThreeAndFiveReplaedWithFizzBuzz
	-- remainingNumbersAreUnchanged

	-- Imho No amount of tests can explain fizzbuzz better than a declarative implementation:
	fizz :: Int -> String

	module Collatz where

	import Control.Monad.Writer

	collatzSeq :: Integer -> Writer [Integer] Integer
	collatzSeq n = do
	n <- collatz n
	if n==1 then return 1 else collatzSeq n

	collatz :: Integer -> Writer [Integer] Integer

	https://github.com/gigasquid/wonderland-clojure-katas
	http://exercism.io
	http://archkatas.herokuapp.com

	-- Given a list of phone numbers, determine if it is consistent.
	-- In a consistent phone list no number is a prefix of another. For example:
	-- Bob 91 12 54 26
	-- Alice 97 625 992
	-- Emergency 911
	-- In this case, it is not possible to call Bob because the phone exchange
	-- would direct your call to the emergency line as soon as you dialled the
	-- first three digits of Bob's phone number. So this list would not be consistent.